The High Court of Justice on Sunday ordered the state to respond within five days to a petition submitted by dozens of human rights groups requesting that Israel halt its cutoff of fuel supplies to the Gaza Strip.

Israel began cutting deliveries in vital fuel supplies to Gaza earlier Sunday, following through on a promise to step up pressure on Gaza's Hamas rulers in response to months of Palestinian rocket attacks, Israeli and Palestinian officials confirmed.

Ahmed Ali, the deputy director of Gaza's Petroleum Authority, said shipments of diesel fuel and gasoline were 30 percent smaller than regular deliveries.

He warned the cuts would cause widespread hardship in impoverished Gaza.

Following the commencement of the fuel cutoff, dozens of human rights organizations petitioned the High Court of Justice demanding that the Israel Defense Forces halt the cessation of fuel and electricity supplies.

According to the rights groups, the decision to cut off vital power supplies is illegal and could likely harm the innocent civilian population in the embattled Gaza Strip.

Dor Alon, Defense Ministry confirm cutoff

Dor Alon, the Israeli energy company that provides fuel to Gaza, confirmed Sunday that it had begun the cutoff under orders from Defense Ministry.

The Defense Ministry said in a statement Sunday that the Sufa crossing between Gaza and Israel, used for transporting fuel, has been closed. Last week, Defense Minister Ehud Barak gave a green light for cuts to Gaza's fuel and electricity supplies.

"In line with the Israeli government's decision, the Defense Ministry will this week begin cutting fuel supplies to the Gaza Strip by between 5 and 11 percent, depending on the type of fuel," an Israeli security source said.

Government spokeswoman Miri Eisin said Sunday that Israel would not allow in any way a humanitarian crisis to develop in Gaza. "The terrorists are bombarding the crossing points of the fuels, and we do not feel the need to supply the terrorists," she said.

Mojahed Salama, head of the Palestinian Authority's Petrol Agency, said earlier Sunday that the fuel imports showed a 40 to 50 percent reduction in diesel and benzine supplies and a 12 percent reduction in fuel for Gaza's power plant. There was no immediate obvious impact on electricity supply.

"We sent the supplying company the same daily requests but they said they were sorry and that because of the new imposed sanctions they could only send us a reduced quantity," Salama said.

Gaza residents have begun to form lines at gasoline stations, stocking up for the imminent shortage. Intermittent power outages were also reported along the Strip, but it is not yet clear whether this is intentional.

Earlier Sunday, Israel denied having cut the fuel supply supply to Gaza. "No instructions have been received from the defense minister, and therefore there have not been any cutbacks," said Captain Shahdi Yassin, spokesman for the Israeli Defense Ministry office that liaises with the Palestinian Authority.

Israel says it is seeking non-violent ways of pressuring Hamas, an Islamist group that seized control of Gaza in a June civil war, to stop cross-border rocket salvoes by Palestinian militants.

Gaza's power plant received a full supply of fuel on Sunday, officials with the European-funded fuel supply program said.

"The plant received the full amount for today. It was delivered," said a senior European Union official involved in overseeing the program.

The United Nations has told Israel it must not inflict collective punishment by denying vital supplies to Gaza's 1.5 million residents.

Deputy Defense Minister Matan Vilnai told Israel Radio on Saturday that the government's decision to periodically cut the flow of electricity to the Gaza Strip is another step in Israel's disengaging from responsibility for the area, and is not part of a policy of collective punishment.

Vilnai said he does not expect the latest sanctions to halt the continuing rocket fire from the Gaza Strip, and added that the limits placed on fuel and electricity supplies will be implemented either Sunday or Monday. The decision is pending legal approval.

Prime Minister Ehud Olmert promised Palestinian Authority Chairman Mahmoud Abbas that Israel would not cut off power to hospitals or cause a humanitarian crisis in the Gaza Strip, despite the limited power cuts.

Olmert made the pledge over a working lunch with Abbas at his Jerusalem residence, a government official said, speaking on condition of anonymity as the meeting was closed to media coverage.

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